A dive-in-at-the-deep-end education in the nitty-gritty workings of an Operating System.

"What I cannot create I do not understand"

All code is heavily commented to provide an educational commentary of exactly what is going on. Please dive in.

• A custom-written but fairly standard boot loader
• A screen driver for outputting to the screen
• A port driver for communicating with various I/O chips: PIT, PIC, the screen etc
• Excpetion handlers
• Interrupt handlers, supporting a timer & keyboard input

Requires qemu to be installed:

On Mac:

brew install qemu

You'll also need these cross compilers so that you can compile for your target. On Mac you can get them pre-built.

brew tap nativeos/i386-elf-toolchain
brew install i386-elf-binutils i386-elf-gcc i386-elf-gdb

• make run to run the Operating System in QEMU

• make run-debug to run with debugger listener. Execution will halt until the debugger is attached. Run the QEMU attach debug configuration included in the .vscode/launch.json. The process execution will begin and you now have debug capability from your editor.

In the tools folder you'll find some useful resources for further explanation of all of this.

There are also some scripts for disassembly which are useful too.